Vulnerabilities > CVE-2017-9391 - Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability in Getvera Veraedge Firmware and Veralite Firmware

047910
CVSS 9.0 - CRITICAL
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
SINGLE
Confidentiality impact
COMPLETE
Integrity impact
COMPLETE
Availability impact
COMPLETE
network
low complexity
getvera
CWE-119
critical

Summary

An issue was discovered on Vera VeraEdge 1.7.19 and Veralite 1.7.481 devices. The device provides UPnP services that are available on port 3480 and can also be accessed via port 80 using the url "/port_3480". It seems that the UPnP services provide "request_image" as one of the service actions for a normal user to retrieve an image from a camera that is controlled by the controller. It seems that the "URL" parameter passed in the query string is not sanitized and is stored on the stack which allows an attacker to overflow the buffer. The function "LU::Generic_IP_Camera_Manager::REQ_Image" is activated when the lu_request_image is passed as the "id" parameter in query string. This function then calls "LU::Generic_IP_Camera_Manager::GetUrlFromArguments" and passes a "pointer" to the function where it will be allowed to store the value from the URL parameter. This pointer is passed as the second parameter $a2 to the function "LU::Generic_IP_Camera_Manager::GetUrlFromArguments". However, neither the callee or the caller in this case performs a simple length check and as a result an attacker who is able to send more than 1336 characters can easily overflow the values stored on the stack including the $RA value and thus execute code on the device.

Vulnerable Configurations

Part Description Count
OS
Getvera
2
Hardware
Getvera
2

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Buffer Overflow via Environment Variables
    This attack pattern involves causing a buffer overflow through manipulation of environment variables. Once the attacker finds that they can modify an environment variable, they may try to overflow associated buffers. This attack leverages implicit trust often placed in environment variables.
  • Overflow Buffers
    Buffer Overflow attacks target improper or missing bounds checking on buffer operations, typically triggered by input injected by an attacker. As a consequence, an attacker is able to write past the boundaries of allocated buffer regions in memory, causing a program crash or potentially redirection of execution as per the attackers' choice.
  • Client-side Injection-induced Buffer Overflow
    This type of attack exploits a buffer overflow vulnerability in targeted client software through injection of malicious content from a custom-built hostile service.
  • Filter Failure through Buffer Overflow
    In this attack, the idea is to cause an active filter to fail by causing an oversized transaction. An attacker may try to feed overly long input strings to the program in an attempt to overwhelm the filter (by causing a buffer overflow) and hoping that the filter does not fail securely (i.e. the user input is let into the system unfiltered).
  • MIME Conversion
    An attacker exploits a weakness in the MIME conversion routine to cause a buffer overflow and gain control over the mail server machine. The MIME system is designed to allow various different information formats to be interpreted and sent via e-mail. Attack points exist when data are converted to MIME compatible format and back.